Solid State Regulator $25.94

[pamcopete]

63a

Well, I'm not sure that I follow you. The power to the ignition switch comes from the battery, through a fuse, it does not come from the regulator. The ign switch provides battery power TO the regulator, which in turn provides current to the brushes in the alternator. The output of the alternator goes through the rectifier diodes and then through the main fuse to the battery.

So, as long as your battery is capable of producing enough current to keep the headlight on and power the coils, you can continue riding, at least to head home and fix the problem.

If the alternator or regulator or rectifier fail, then you should disconnect the regulator so it is not drawing current uselessly, thus keeping whatever is in the battery available for the headlight and coils.

There have been a lot of posts that talk about how long your battery will last if the alternator fails, but the only sure way to know is to try it. Disconnect the regulator and see how long the engine runs. Ride around the block a few times so you are close to home when it quits. Recharge the battery with a trickle charger after the test. Subtract about 15 minutes from the time, because that is about how long it will take for you to even realize that the alternator has quit.

[63a]

Thanks for the clarification. For some reason, I thought you diagram above meant the ignition switch was getting power from the regulator vs the switch providing power to the VR. Now it makes sense. Sorry for the dumb question. I really appreciate your posts-very helpful.

[pamcopete]

63a

Well, the diagram could be a little confusing, so I changed it to read "from Ign Switch" with the arrow going the other way. Also added the note that the output from the rectifier must go through a fuse to the battery.

[63a]

Probably only confusing to me but thanks for the clarification. What indications would occur that the alternator/VR/rectifier has failed? It seems the failure would be transparent to the rider (until the lights begin to dim for a points ignition) unless an idiot light, voltmeter, or ammeter was in the system to indicate a problem. I did not plan to add any of those to my system but I am thinking an idiot light showing a battery discharge versus charge situation could be useful. Now, I just need to figure out how to add this light to the system.

What amp fuse would you recommend between the VR and battery and also in the main wire from the battery to the ignition switch?

[pamcopete]

63a

Well, the main fuse should be a 20 A fuse, just like stock. I would also recommend a separate 20 amp fuse from the rectifier to the battery, so if it blows, you will still have power from the battery.

A meter would be useful because you are going to have to keep an eye on that tiny battery when stooped at a light.



This is the meter I installed on my bike with a bracket fashioned from a piece of aluminum angle screwed under the idiot light housing. It's from www.martelcorp.com I also wired a diode to my safety relay so the white headlight lamp comes on if the charging system fails. If you were not planning on using the safety relay, you could use it to turn on a lamp when the alternator is not working.

[63a]

I'm building the wiring harness from scratch so I will need to look at a wiring diagram to see the safety relay. What is the location and purpose of the safety relay in the stock system?

I haven't seen any simplified XS650 wiring diagrams that have the idiot light so I may need to get creative for that one. I think I need a light that comes on when the sytem voltage drops below a certain point (12.5 volts or so) but I'm not sure how to make that happen. Maybe a relay that requires 12.5-13 volts to remain open so that a voltage drop below that would allow the relay to close and make a connection (ground or power side) for a small bulb or an LED.

[pamcopete]

63a

In the stock setup, the safety relay operates from the yellow wire from the alternator when the alternator is producing an output. It supplies battery voltage to the starter relay when the alternator is not producing an output, IE the engine isn't running, so prevents you from engaging the starter when th engine is running. And it turns on the headlight after the engine has started. If you connected a lamp to the contact that normally provides battery to the starter relay, then the lamp would come on if the regulator, rotor or stator failed, but it is not sensitive to battery voltage.

[63a]

If I understand correctly, I should be able to connect the yellow wire from the alternator to a idiot light and the light would only be lit when the alternator is not producing output. I will give it a shot and see what happens.

I really appreciate your help.

[pamcopete]

63a

No, no....just the opposit.....the yellow wire has a very small AC voltage when the alternator IS running and producing an output, so you have to have the safety relay to turn the light off when the alternator is producing an output.

[63a]

Got it. Thanks for the clarification. I have remnants of a stock XS650 wiring harness so I'll see if I can find the safety relay.

Thanks again for all your help.

[jeepurze]

could you look at this rough sketch of what im shooting for. I had to scan this at work so its a rough sketch , not the normal quality crayola drawings I normally do. ;D ;D
no elect start, no keyed switch. thanks jeep.

[jeepurze]

sorry about the small pic, im not really good at scanning . also the on off switch is simplified in sketch, im planning on using a really cool antique tractor switch thats got 3 positions, but ive got to figure out that part too, I wasnt sure if fuse is before or after switch.

[leaddirt]

this is a example

www.wiringharnesses.com/switches.htm[/img]
www.wiringharnesses.com/images/S60820_Key_Switch.JPG
Key Switch
3-position OFF,ON,START fits 13/16" hole
Fits Ford
$
21.00
AG95534

[pamcopete]

jeepurze

Here is another wiring diagram for the Reg/Rect. Hope it makes it more understandable:

[jeepurze]

pamcopete said:

jeepurze

Here is another wiring diagram for the Reg/Rect. Hope it makes it more understandable

I can then attach fuse @ brown wire to acc's and then this goes to coil? the X where the ig switch would be is replaced with on/off switch. (i will also hide a kill switch in a top secret spot)
that sheds some light on it I couldnt figure out where power was coming from.